Forced-draft-producing device



Sept. 30, 1930. .1. w. BRAGSTAD FORCED DRAFT Pnonucme nEvIcE Filed'April 17. 1929 2 Sheets-Sheet l To Hlm/162' Sept. 30, 1930. Tg. w. BRAGsTAD FORCED DRAFT PRODUGING DEVICE Filed April 1'7. 1929` s shuts-Sheer. 2

T0 SOURCE 0F' CHIPRE/VT @7220?? MM f fgfaci um? Patented sept. 3o, v1930 f l JOSEPH W. BRAGSTAD, or Eri/inciter, ILLINois l FORCED-DRAFT-Pnonucme DEVICE l Application med Aprni?,

1 5 one of the objects of the invention is to provide improved means for drawingco-ld air out of ahouse or room and for forcing warm l air thereinto. Y

A further object is to provide an improved 10 device of this character having means toy prevent what is commonly known as lback lash of the air, to prevent the heated air from obstructing or forcing back the in,- flow of cold air, and thereby insure a fcir- "15 culation of the air.

A further object is to provide an improved filter device for the air supply to the fan. To the attainment of these ends and the accomplishment of other new and useful objects 20 as will appear, the invention consistsin the features of novelty in substantially the construction, combination and arrangement of the several parts hereinafter more fully described and claimed and shown in the accompanying `drawings illustrating Vthis invent tion'andin which Figure 1 is a view partly in elevation and partly in section of a device of this character constructed -inaccordancefwith the princi ples of this invention and showing the same as used in connection with a flue and with parts omitted. t f o Fig. 2 is Va Aview taken on line 252, F 1gure 4;, withparts omitted. j a

Figure 3 is a View similar to Figure 2, showing the operating mechanism for the dampers. l

" Figure 4 is a sectional view taken on line 4 4, Figure 2,- with parts in elevationl lFigure 5 is an enlarged detail sectional view taken on line 5 5, Figure 1.

Figure y6`is an enlarged detail sectional view showing the manner .of Ysecuring the filter casing to the fan casing.v p

Referring more particularly to the drawings the numeral 10 designates generally a flue of any desired size and configuration for receiving and conducting cold air away from a room orfhouse. This flue 10 may have communication wlth a room through the 1929. serial No. 355,789.

`floor 11` thereof and by Ameans ofthe ordi- "il nary air registers or grating 12. ,t

The liue may loe.` of any desired size and configuration and communicating therewith may be additional flues 13a-14; leading'from other points of supply of cold air.`V

Arranged adjacent the bottom of the flue in an opening15 and suitably supported isa o casing 16 which has communication with the opening 15 at onetend, and isv provided with Aan outlet opening 17athrough which latter air :circulated through the flue 10 will be directed to a furnace` t The casing 16 isl of. an desired size and configuration `but `is pre erably angular in cross section and. arranged within the casing 16vis a fan ,casing 17 Whichis of a diameter to' occupy only a portion of the crossv sectional area of the casing or passagel.A The fan casing 17 is ypreferably circular m cross section and in order that it may conform tothe contour of the casing or passage Y16 ller members 18 may be formed on the outside of thefancasing. f e

Uprights 19 may be arranged in the casing or passage 16A Ato abut the portions 1,8Vof the fan casing and alsothe'periphery vof the latter for holdingthe fan casing inposition. The fan `casingl7 preferablyprojects be`- yond the casing or passage 16 at the entrance end Vof .the'la'tter and arranged in the fan casing a motor 20,-for operating the fan The motor may besupported in anyrsuitable manner preferably by means of brackets 22 which passthrough suitable openings 2,3 inthe Vbottom `of the casing` or passage l6and are embedded in plastic material 24 such as cement, concrete or the like, the free extremities of the brackets 22 being preferably de# flected as at 25 to form anchors for the brackets. t

Encompassing the anchoring material 24, 4which latter may be arranged within the ground 26, is a filling material such as sand, gravel or thelike. t

The openings 2 3 in the wall of the casing or passage 16 are of a size somewhat greater than the dimensions ofthe brackets22 so that A the brackets will be held out of contact with` Vspaced stopsv35 on the walls of the opening to prevent vibration of the brackets against the casing wall. Similarly the fan casing 17 is provided with openings through which the brackets 22 pass and these openings are also of a size to prevent the walls of the opening from contacting with the brackets. 4 v;

Arranged in the casing orpassage 16 and between the uprights 19 and the lateral walls of the casing or passage 16, are dampers 28 which are swingingly` supported by means of suitable hinges 29 and springs 8 0 may be provided, one end of which is secured to the respective dampers 28 and the otherend of each is anchored as at 31 to a fixed support preferably the upright walls ofthe casing or passage 16. v

yThese springs 30 tendnormally to move the d'ampers 28 in a direction to close Vthe passagebetween the fan casing and the outer casing or passage `16, suitablestops 32 being provided/for limiting the movement of the dampers 28 under the stress' of the springs The damper-s 28 are provided to prevent a back lash of the heated air currents and to prevent the-'heated air'frominterrupting or obstructingthe flow of cold air currents through the passage or casing 16.

Flexible members 384 are connected with the dampers 28 and these members in turn may be connectedtov a kcontrol element 84 by means of which the dampers 28 may be operated from aremote point and against the stress of the springs 30. The operation of the dampers 28 will, through the medium of the member 34, operate upon a switch lever 36 to control the operation of a switch 87, which in turn controls the operation of the motor.

It has been found in and foreign matters to bel drawn from the room and discharged through the fan casing. Y

In order to overcome this objection there Vis provided a tubular filter 38 which is con- Ywhile the end 40 thereof is open.,v` This open end -40of the lter telescopes over a flange 41 on the inlet endl of the fan casing 17 and a rsuitable fastening means such as a draw string, or other suitable element, may be provided for holding the end of the filterV 39 against accidental detachment from the anged end 41 of the fan casing 17.

The filter 38 may be of any desired length and projects for a considerable distance beyond the inlet end of the fan casing so as to enter and be disposed within the flue 10.

A flexible member 43 is connected by one end as at 44 with the end of the filter and the flexible member passes over pulleys 45-46, within the flue 10 to another pulley 47 adjacent the bottom of the flue so that the end devices ofthis char? racter that the fan causes considerable dust 39 of the filter may be raised and lowered within the flue 1() and maintained in its adjusted position. An opening 48 is provided inthe flue 10 and is closed by means of a closure 49 and through the medium of which closure 49 and opening 48 access may be had to the filter to remove the samewhen desired.

An anchor 50 rmay be provided for anchoring a portion of the filter so that it will not be drawn into the flue and to prevent it frombecoming.detached from the fancasing 17.

VIf desired and in order to maintain the filter against collapsing rings 51 constructed of any suitable material, are provided land are arranged at spacedv intervals in directions lengthwise of the filterz These rings may be secured in position in any suitable manner such as by means of a fastening device 52 such as a fiexiblemember or the like and the rings may be arranged either on the inside or the outside of the filter.

The filter is of a diameter considerably less than the internal diameter of the fine 10 so that the air currents lbeing drawn into the flue 10 will pass into the filter' 88 from the outside thereof and throughout the length of the filter.

With this improved construction it will be manifest that by adjusting the dampersf 28 kthe circulation of the air currents may be controlled and by the provision of the filter the air will be filtered before it reaches the fan.

The filter `being extended, vpresents an extended surface through which the air may be .filtered and being flexible maybe raised -and lowered in the flue to any desir-ed height and may be readily removed from the flue and detached from the fan casing 17 through the door opening 48.

It has been found that by locating the fan .21 ina position that it will project or stand slightly beyond the outlet end of the casing or in a position where it will be in close proximity Vtothe end but'spaced slightly therefrom, the airV currents will be thrown `,out radiallyV toward the wall of the casing or passage 16, with the result that the air will be equally distributed at all points around the base of the furnaoewith which the casing or passage 16 has communication. l

If the air currents are not so distributed, but if they leave the fan casing in a direct line with the fan, the air currents will strike one spot or area on the fire pot wall, with the result that the wall will warp and there will be a leak. That is, it will be hotter onv 'the two sides or areas which are not contacted 'by thedirect blast of air.

While the preferred form of the invention has been herein shown and described, it is to be understood that various changes may be .L name to this specification,

made in the details of construction and in the combination and arrangement of the several parts, Within the scope of the claims, Without departing from the spirit of this invention.

d What is claimed as new is 1. An apparatus of the characterdescribed embodying an air passage, a fan casing occupying onlya portion of the cross sectional area of the passage, and a tubular filter fitting over and forming a closure for the inlet end of the fan casing, the inlet of the fan casing being disposed adjacent a flue and into Vwhich Hue the said lter projects beyond the fan casing.

2. An apparatus of the character described embodying` an air passage, a fan casing occupying only a portion of the cross sectional area of the passage, avtubular flexible, filter litting over and extending beyond the fan casing and into a flue, means for supporting the free end of the filter in the flue, and means for maintaining the filter against collapsing.

3. ln combination an extended flue, a fan casing adjacent and having communication With the fine, a tubular flexible lilter open at cne end, said end being securedto and having communication With the inlet endof the fan casing to form a closure therefor, said iilter extending into the flue beyond the fan casing, and means for raising and lowering the end of the lter in the flue and Vfor supporting said end of the ilter.

In testimony whereof I have signed my April, A. D. 1929.

JOSEPH W. BRAGSTAD.

on this 12th day ofv 

